1-s2.0-S0958946502000136-main-libre

8/12/2019 1-s2.0-S0958946502000136-main-libre

1/8

A new method for the mix design of medium strengthowing concrete with low cement content

Nan Su a , Buquan Miao b, *a Department of Construction Engineering, National Yunlin University of Science and Technology, 123, Sec. 3, University Road, Touliu,

Yunlin 640, Taiwan, ROC b Department of Civil Engineering, University of Moncton, Moncton, NB, Canada E1A 3E9

Received 4 September 2001; accepted 20 October 2001

AbstractThe market for medium strength (2835 MPa) concrete with high workability is recently increasing due to its qualitative and

cost-saving advantages. This paper proposes a new mix design method for medium strength owing concrete (FC) with low cementcontent. The proposed method determines the packing factor (aggregate content) rst, and then lls binding paste containing y ashand GGBS into the voids between aggregates to make concrete that has the desired workability and strength. Tests on slump, slumpow, and compressive strength were carried out and the results indicate that medium strength FC can be produced successfully usingthis method. Concrete mixtures designed by using the proposed method requires a small quantity of binder and is therefore veryeconomical.

2002 Published by Elsevier Science Ltd.

Keywords: Flowing concrete; Mix design; Medium strength; Packing factor; Slump; Slump ow; Compressive strength; Fly ash; GGBS

1. Introduction

Concrete is the dominant construction material todaywith an annual worldwide production of over 4.5 billionmetric tons [1]. However, traditional concrete with highwater to cement ratio (water content) and low work-ability is difficult to place and less durable. Largeamounts of labor and energy are required for the placingof such concrete. Quality problems such as honeycomb,bleeding, and segregation sometimes occur. To solvethese problems, concretes with high workability andhigh durability, such as high-performance concrete(HPC) and self-compacting concrete have recentlybeen developed with the aid of superplasticizer (SP), butthese types of concrete are presently expensive andrequire intense quality control [26]. Pollution is anotherproblem associated with current concrete mixes. Harm-ful gases such as CO 2, SO 2, NO 2 and mill dusts aredischarged into the atmosphere during the production of cement. The energy content of cement and aggregate are

about 1300 and 8 kW h/t [1]. It is therefore important toreduce the cement content of concrete through propermix proportions using industrial by-products such asy ash (FA) and ground granulated blast-furnace slag(GGBS), efficiently contributing to global sustainabledevelopment [7,8]. Hence, medium strength owingconcrete (FC) or high workability concrete with a lowcement content and a high content of cement replace-ment materials such as FA and GGBS would be aneconomical way to produce durable concrete.

Mix design methods such as those proposed by theACI committee [9] for normal strength concrete are notsuitable for proportioning concrete with high workability[10]. Many mix design methods based on different as-sumptions for high workable concrete like HPC havebeen proposed by Metha and Aitcin [2], the LaboratoireCentral des Ponts et Chaussees (LCPC) [11], the SwedishCement and Concrete Research Institute (CBI) [12], andBharatkumar et al. [13]. These methods have proven to besuccessful in their own elds of application, but they oftenlead to a high paste volume if applied to medium strengthFC, and are then neither economical nor durable.

This paper proposes a mix design method for mediumstrength FC with low cement content. After presenting

* Corresponding author. Tel.: +1-506-858-4326; fax: +1-506-858-4082.

E-mail address: [email protected] (B. Miao).

0958-9465/03/$ - see front matter 2002 Published by Elsevier Science Ltd.PII: S0958-94 65(02 )0001 3-6

Cement & Concrete Composites 25 (2003) 215222www.elsevier.com/locate/cemconcomp
http://mail%20to:%[email protected]/http://mail%20to:%[email protected]/

8/12/2019 1-s2.0-S0958946502000136-main-libre

2/8

the general considerations, the mix proportion proce-dures will be developed, followed by sample calculationsand validation experiments. Finally, the effects of dif-ferent factors on the workability and the strength of theconcrete will be discussed.

2. General considerations

Concrete can be considered as a two phases material:aggregates and binding paste. The purpose of concretemix design is to nd the optimum proportion of eachingredient to meet the client s requirements with regardto workability, strength, durability, cost, and ecology.For FC, the requirement on workability is often moredifficult to meet than the need for strength. That s whythe proposed method starts with aggregate content, themost important parameter for workability. The work-ability of concrete can be characterized by its packingfactor, dened in this study as the mass ratio of aggre-gate at a tightly packed state to that at a loosely packedstate.

As industrial by-products, FA and GGBS are abun-dant in most countries in the world and are proven tosignicantly improve the workability and durability of concrete in an economical and an ecological way [1,8].Thus, large amounts of FA and GGBS will be used inthe proposed method. Because the Pozzolanic reactionof FA and GGBS is much slower that the hydrationof cement [1,8], their contribution to the compressivestrength of concrete is secondary as compared to that

of cement, especially at 28 days when compressivestrength is specied for normal strength concrete.Therefore, the proposed method considers cement as theprimary provider of the compressive strength of con-crete while FA and GGBS provides its workability.Water will be added to the FA and GGBS until they areas uid as the cement paste.

3. Procedures of the proposed method

The principal consideration of the proposed methodis to ll optimum amounts of binding paste into voids of aggregate framework loosely piled to satisfy the requiredproperties of concrete with regard to workability andstrength. The compressive strength of concrete at 28days will be provided by the water/cement ratio and thecement content while the uidity of fresh concrete willbe provided by the volume ratio of aggregate to bindingpaste and the SP dosage. The use of FA and GGBSis based on durability, ecological, and economic con-siderations. They will be used to improve the uidityand anti-segregation capabilities, not the compressivestrength. Water will be added to FA and GGBS untilthey are as uid as the cement paste. With the proposed

method, all that needs to be done is to select theappropriate materials, do the calculations, conduct trialbatches and make some adjustments, and FC of medium

strength can be obtained. The owchart of the proposedmix design method is presented in Fig. 1 and detailedprocedures are summarized in the following steps.

Step 1: Calculation of coarse and ne aggregate contents

A higher PF value would imply a greater amount of coarse and ne aggregates used, thus decreasing thecontent of binding paste in FC. Consequently, its u-idity will be reduced. On the other hand, a low PF valuewould mean increased uidity of concrete for the sameconsistency of binding paste. Therefore, it is important

to select the optimal PF value to meet the requiredproperties in mix design. The content of ne and coarseaggregates can be calculated as follows:

Af PF AfoV Af V A

1

Ac PF Aco1 V Af

V A 2where Af is the content of ne aggregates, Ac is thecontent of coarse aggregates, Aco is the unit weight of loosely piled saturated surface-dry (SSD) coarse aggre-gate, Afo is the unit weight of loosely piled SSD ne

Fig. 1. Flowchart of the proposed mix design method.

216 N. Su, B. Miao / Cement & Concrete Composites 25 (2003) 215222

8/12/2019 1-s2.0-S0958946502000136-main-libre

3/8

aggregate, PF is the packing factor, the ratio of mass of aggregates in the mixture to that of loosely packed stateaccording to ASTM C-29, 1.141.22 for FC [14], V Af =V Ais the volume ratio of ne aggregate to total aggregate.

Step 2: Calculation of cement content

Cement is regarded as the primary provider of thecompressive strength of concrete. However, concretewith too much cement is neither economical nor dura-ble. The proposed method suggests using minimum ce-ment content for strength requirement. If a compressivestrength of x MPa at 28 d is expected for each kilogramof cement used, the cement content will be

C f 0c x

3

where C is the cement content (kg/m 3), f 0c is the speciedcompressive strength of concrete at 28 days (MPa), x is

the compressive strength provided by each kilogram of cement, in MPa, 0.110.14 MPa (1520 psi) for FC usedin Taiwan [14].

Step 3: Selection of water/cement ratio

The required average compressive strength f 0cr mustrst be determined from the specied strength f 0c andvariation on concrete strength during the production inthe ready-mixed concrete plant. This can be done ac-cording to the method suggested by ACI 319-95 [15] asfollows:

f 0cr max f 0c 1:34S ; f 0c 2:33S 35 MPa 4where S is the standard deviation (MPa).

The relationship between f 0cr at 28 d and water/cementratio for FC was obtained from previous experiments[16] and is presented on Fig. 2; this relationship is similarto that proposed by ACI 211.1 [9]. However, the selectedwater/cement ratio must satisfy both the strength andthe durability criteria. Due to the lack of data on the

durability of FC, the values can be taken from ACI211.1 [9] in this study.

Step 4: Calculation of mixing water content required bycement

The content of mixing water required by cement canthen be obtained using

W c W c

C C 5where W c is the content of mixing water required bycement (kg/m 3), W c=C is the water to cement ratio byweight.

Step 5: Calculation of FA and GGBS contents

To obtain the required workability and segregationresistance, FA and GGBS are used to increase the bin-

der content. Then the paste volume of Pozzolanic ma-terials ( V pp ) can be calculated as follows:

V pp 1 Aco

1000 G Ac Afo

1000 G Af C

1000 G c W c

1000 G wV a n

C P 1000 G sp

6

where V pp is the volume of FA and GGBS paste, G Ac isthe specic gravity of coarse aggregates, G Af is the spe-cic gravity of ne aggregates, G c is the specic gravityof cement, G w is the specic gravity of water, G sp is thespecic gravity of superplasticizer (liquid), V a is the air

content (%), P is the amount of FA and GGBS (kg/m3),

n is the dosage of SP based on binder content (%).In order to get the FA and GGBS paste with water/

binder ratio of W f = F and W s=S as owable as the cementpaste, ow tests (ASTM C230) should be carried out. If the total amount of pozzolan materials (FA and GGBS)in FC is P , where FA occupies A% and GGBS occupies1 A%, the adequate ratio of these two materials can beestablished through testing or according to previousexperience [16].

V pp 1 W f F

A% P

1000 G f 1

W sS

1 A% P 1000 G s

7

where G f , G s, G c, W f = F , W s=S and A% can be obtainedfrom tests.

Let Eq. (6) equals Eq. (7), the total amount of Po-zzolanic materials P in FC can be obtained. Hence, FAcontent ( F ) and GGBS content ( S ) can be calculated asfollows:

F A% P 8

S 1 A% P 9Fig. 2. Relation between compressive strength and water to cementratio.

N. Su, B. Miao / Cement & Concrete Composites 25 (2003) 215222 217

8/12/2019 1-s2.0-S0958946502000136-main-libre

4/8

Mixing water content required for FA paste

W f W f = F F 10

Mixing water content required for GGBS paste

W s W s=S S 11

Step 6: Calculation of SP dosage

The SP can be deduced from the dosage at the satu-ration point from previous tests as Fig. 3. If the dosageof SP used is n% of the binder (cementitious material),and the solid content of SP is m%, then the SP dosage(W sp ) by liquid can be obtained as follows:

SP nC P 12

Step 7: Calculation of mixing water content needed in FC

The water content required by FC is the total amountof water needed for cement, FA and GGBS minus thatin SP. Therefore, it can be calculated as follows:

W W c W f W s 1 mnC P 13

Previous experiences have shown that a total watercontent of 168181 kg/m 3 is suitable for FC [17].

Step 8: Adjustments for aggregate moisture

The mix proportions determined by steps 16 aretherefore based on the SSD condition of aggregates.

Mixing water content should be adjusted according tothe moisture content of aggregates and the amount of SP at the ready-mixed concrete plant or constructionsite.

Step 9: Trial batch adjustments

Evaluation of the trial mixes should be based onthe criteria of workability (slump and slump ow) andcompressive strength. Accordingly, adjustments should

be made on PF value, water to cement ratio, cementcontent, ne/coarse aggregate ratio, and SP dosage.When a mixture satisfying the desired criteria of work-ability and strength is obtained, the mix proportions of the laboratory-sized trial batch are scaled up for pro-ducing full-sized eld batches.

4. Sample computations

A concrete of 28 MPa with slump of 240 20 mmand slump ow of 600 50 mm were specied. Locallyavailable Type I Portland cement, Class F FA, andGGBS with specic gravity of 3.15, 2.15, and 2.92 wereused. Their physical properties and chemical composi-tions are shown in Table 1. The SP used was napha-thalene-type with a solid content of 40% and specicgravity of 1.064. The coarse aggregate used was a cru-

shed river gravel with a specic gravity of 2.66, maxi-mum size of 25 mm and loose unit weight of 1581 kg/m 3

(ASTM C29). The ne aggregate was a river sand hav-ing a specic gravity of 2.63 at SSD condition, a nenessmodulus of 3.2 and a loose unit weight of 1483 kg/m 3 .Table 2 shows their gradations. The volume ratio of neto coarse aggregate was chosen to be 52:48. The con-struction is a reinforced concrete footing continuouslyexposed to wet conditions but no freezing and thawing.Steps 17 compute the mix proportions with PF 1:18as follows:

Step 1: Assume PF 1:18

Fine aggregate content : Af 1483 1:18 52%

910 kg =m3

Coarse aggregate content : Ac 1581 1:18 1 0:52 896 kg =m3

Step 2: Each kilogram of cement is expected to pro-vide 0.14 MPa compressive strength at 28 days [14].

Cement content : C 280:14

200 kg =m3

Step 3: Assuming 3.5 MPa standard deviation frompast experience, the required average strength ( f 0cr )should be

f 0cr max 28 1:34 3:5; 28 2:33 3:5 3:5

32:7 MPa

From Fig. 2, the water/cement ratio is 0.50 basedon the required compressive strength of 32.7 MPa. Theselected W c=C (0.50) satises the durability criteria of ACI 211.1 for the given type of exposure conditions[9,16].Fig. 3. Effect of SP dosage on the workability of concrete.


8/12/2019 1-s2.0-S0958946502000136-main-libre

5/8

Step 4: Mixing water amount for cement: W c 0:50 200 100 kg/m 3

Step 5: Entrapped air was estimated to be 1.8%. Theoptimum dosage of liquid SP equals 1.7% found fromFig. 3. The paste volume of Pozzolanic materials (FAand GGBS) can be expressed as follows:

V pp 1 9102660

8962630

2003150

10010000

0:018

0:017 1 0:4 200 P

1064 14

According to the ow table tests with the same dos-age of SP, a water/binder ratio ( W f = F ) of 0.52 for FA

paste and of 0.42 ( W s=S ) for GGBS paste were found toobtain the same ow value for the cement paste withW c=C 0:50. From Fig. 4, the optimum FA to GGBS(by weight) of 1:1 was obtained based on the compres-sive strength of concrete. The paste volume of Pozzol-anic materials is

V pp 1 0:520:5 P 2150

1 0:420:5 P 2920

15

Let (14) equals (15), one gets the amount of Pozzolanicmaterials:

P 155 kg =m3

Thus, the FA and GGBS content: F S 0:5155 77:5 kg/m 3.

Step 6: Dosage of SP: W sp 0:017200 77:5 77:5 6:0 kg/m 3

Step 7: Mixing water content: W 100 40:3 32:6 1 0:46:0 169 kg/m 3

Mix proportions were also calculated for different PFvalues from 1.14 to 1.22 and presented in Table 3.

5. Experimental program

In order to verify the validity of the proposed mixdesign method, a set of FC mixes based on the aboveprocedures was prepared. The properties of the rawmaterials used were described in the previous section.The slump and slump ow as well as the air contentof fresh concrete were tested. Standard cylinders of 150 300 mm for compressive tests were preparedand cured in lime-saturated water until test ages.The procedures followed during those tests are listed inTable 4.

Table 1Properties and compositions of cement, FA and GGBS

Item Materials

Cement FA GGBS

Physical propertiesFineness

Amount retained on a 45um sieve (%)

15 9

Blaine method (cm 2 /g) 3350 422Specic gravity 3.14 2.10 2.93

Chemical compositionLoss on ignition (%) 1.36 5.0 0.4SiO 2 (%) 21.0 55.5 34.8Al 2O 3 (%) 6.26 27.9 13.6Fe 2O3 (%) 3.09 6.3 0.32CaO (%) 64.2 6.3 40.5MgO (%) 1.53 1.6 6.96SO 3 (%) 1.95 0.8 1.52Alkalinity (%) 0.3 1.8Sulde sulfur (%) 0.5Free CaO 1.36

Insoluble residue (%) 0.20

C 3S 46.0 C 2S 26.0 C 3A 11.4 C 4AF 9.4 CSH 4.73

MortarAir content of slag mortar(%)

3.5

Slag activity index in 3 d (%) 72

Table 2

Gradations of aggregates (unit: % passing)Sieve size Coarse aggregates Fine aggregates

1 in. 100 3/4 in. 87.1 1/2 in. 38.4 3/8 in. 25.8 100#4 0.95 98.9#8 0 89.1#16 66.5#30 41.0#50 20.3#100 6.7#200 2.4

Fig. 4. Effect of FA to GGBS ratio on the compressive strength of concrete.


8/12/2019 1-s2.0-S0958946502000136-main-libre

6/8

6. Test results and discussion

6.1. Effect of PF on the workability of concrete

Table 3 shows that a reduction in PF value woulddecrease aggregate content, but increase the content of binding paste, thus enhancing slump and slump ow of FC. Fig. 5 shows that the volume of binding paste has amajor effect on the slump and slump ow of concrete.FC S with good workability were obtained with a pack-ing factor ranging from 1.16 to 1.20 which means a pastevolume from 290 to 310 L/m 3 (Table 5). These resultsagree with those of Okamura [6,18] who suggested apaste volume of 295 L/m 3 or higher for self-compactingconcrete. Mehta and Aitcin [2] suggested a paste volumeof 350 L/m 3 for HPC with a slump of about 180200

mm. From the same Figure, if the same slump wasspecied for a normal strength concrete, a paste volumeas low as 290 L/m 3 would be enough. This agrees withthat suggested by Wu and Lein [19].

When the ratio of slump to slump ow was 0.4 forPF 1:16 1:18, the concrete had better consistency,

plasticity, and owability. The concrete became toosticky when PF P 1:19 with a slump/slump ow ratioP 0.5. In contrast, bleeding and segregation wereobserved on concrete with PF 1:14 slump/slumpflow 0:35 indicating that the paste volume was toohigh. In addition, when PF 1:17, the loss in slump andin slump ow was very low: the slump and slump owwere 240 and 600 mm after mixing; 50 min later, theywere 220 and 580 mm. The best results on workabilityand on slump loss were obtained with PF 1:17. Re-garding slump ow, a value of 600 50 mm was ob-tained for PF ranging from 1.161.18 with a coarseaggregate content from 331337 L/m 3 (Table 5). Theseresults were within the range (300360 L/m 3) suggestedin reference [6] for self-compacting concrete with a 500 650 mm slump ow.

6.2. Effect of PF on the compressive strength of concrete

Fig. 6 shows the compressive strength of FC as af-fected by the PF value. The highest compressive strengthwas observed with PF 1:17 at all concrete ages tested.As mentioned above, the best workability was obtainedwith PF 1:17. When PF 1:14, the compressivestrength of concrete was 1724% lower than that withPF 1:17, probably because the concrete had largeamount of paste and was bleeding slightly and segre-gated. Moreover, the compressive strength of FC withPF 1:22 was 1927% lower than that with PF 1:17probably due to the low workability which could makeconcrete more difficult to compact. At 28 d, the averagecompressive strength of concrete with PF 1:17 was7.2 MPa (27%) higher than the specied strength whichis a reasonable margin for a ready-mixed concreteplant to overcome its strength variation during pro-duction.

Table 3Mix proportions of FC obtained with the proposed method (unit: kg/m 3)

Packingfactor

Coarseaggregates

Fineaggregates

Cement FA GGBS Water SP Water/binderratio

1.14 865 879 200 89 89 180 6.4 0.4761.16 880 895 200 83 83 174 6.2 0.4751.17 888 902 200 79 79 171 6.1 0.478

1.18 895 910 200 76 76 168 6.0 0.4771.19 903 918 200 73 73 165 5.9 0.4771.20 911 925 200 69 69 162 5.8 0.4791.22 926 941 200 63 63 156 5.5 0.479

Table 4Test methods of concrete properties

Item Test method

Slump ASTM C143Slump ow JASS T-503 a

Compressive strength ASTM C39Air content ASTM C231a From Ref. [20].

Fig. 5. Effect of paste volume on the workability of concrete.


8/12/2019 1-s2.0-S0958946502000136-main-libre

7/8

6.3. Air content

The air content of fresh concrete in this study rangedfrom 1.6 to 2.0%, a percentage which approaches theassumption of 1.8% used in the sample calculations.

6.4. Limitation on the proposed method

At the present state-of-the-art, successful fabricationof FC depends on a combination of empirical rules de-rived from experience, laboratory work and a great doseof common sense and observation. Applying step bystep of the procedures of mix design method proposed inthis paper should facilitate the selection of proportionsthat will result in medium strength FC that is workable,strong and economical. In general, the calculated pro-portions should provide a mix having almost the desiredcharacteristics. However, if the cement, FA, or GGBSare not suitable, if the grading of aggregates is not goodenough, if the SP is not efficient enough, if the selectedbinder/SP combination is not fully compatible or someother unexpected factors intervene, the concrete may notreach the desired level of owability. If the concrete doesnot have the desired slump ow and slump, either thePF value should be decreased or the SP dosage in-creased, or else the water content has to be increased as

well as the binder content to keep the same water/binderratio. The workability of the mix may be inadequate dueto a poor shape or gradation of the coarse aggregate, orthe incompatibility of the particular binder/SP combi-nation. In the rst case, the PF value has to be de-creased, and in the second case, the y ash, GGBS, or

the SP should be changed. If fresh concrete bleeds orsegregates, the amount of water, ne aggregate, SPdosage or type, and FA content should be adjusted.However, improvements to these proposed calculationscould always be made.

A local ready-mixed concrete plant has produced FCfollowing the proposed mix design method. Mediumstrength concretes with high workability, low cost andreliable quality were obtained. The results will be pre-sented in a later publication.

7. Conclusions

Based on the results of this study, the followingconclusions can be drawn:

1. Medium strength FC can be obtained using the pro-posed mix design method with cement content of aslow as 200 kg/m 3.

2. The aggregate packing factor determines the aggregatecontent and inuences the workability and strengthof concrete.

3. FC designed with the proposed mix design methodcontains more aggregate but less binder, thus enhanc-ing the economical and ecological advantages.

4. According to the proposed method, medium strengthFC can be produced with a paste volume of 290320L/m 3 with the raw material used.

5. The water content of FC prepared by the proposedmethod is about 168180 kg/m 3 .

6. Concrete mixtures designed by using the proposedmethod requires a small quantity of binder (about370 kg/m 3) and is therefore very economical.

7. The PF value is the controlling factor in the work-ability of concrete. A PF value of 1.161.18 is sug-gested.

Table 5Volume proportions of materials in FC obtained with the proposed method (unit: L/m 3)

Packing factor Coarseaggregates

Fineaggregates

Cement FA GGBS Water SP Paste

1.14 325 334 63.5 41.5 30.5 180 6.0 3211.16 331 340 63.5 38.4 28.3 174 5.8 3101.17 334 343 63.5 36.8 27.1 171 5.7 304

1.18 337 346 63.5 35.3 26.0 168 5.6 2981.19 340 349 63.5 33.8 24.9 165 5.5 2941.20 342 352 63.5 32.2 23.7 162 5.4 2901.22 348 358 63.5 29.2 21.5 156 5.2 275

Fig. 6. Effect of packing factor on the compressive strength of con-crete.


8/12/2019 1-s2.0-S0958946502000136-main-libre

8/8

Acknowledgements

The nancial support of the Golden Ready-MixedConcrete Plant Co. is highly appreciated. The authorsare also indebted to Prof. C.C. Kao and Mr. Z.Y. Liao,National Taiwan University, Prof. K.C. Hsu, NationalTaiwan Normal University, and Mr. T.W. Chang, Na-tional Yunlin University of Science and Technology fortheir assistance during the investigation.

References

[1] Mehta PK. Concrete: structure, properties, and materials. NewJersey: Prince-Hall Inc.; 1986.

[2] Mehta PK, Aitcin PC. Principles underlying production of high-performance concrete. Cement Concrete Aggreg 1990;12(2):708.

[3] Shah SP. High-performance concrete: past, present and future. In:Proceedings of the International Symposium on High Perfor-mance Concrete, The Hong Kong University of Science andTechnology, China. 2000. p. 329.

[4] Aitcin PC. High-Performance Concrete. London: E & FN SPON;1998.

[5] Henry GR. ACI dene high-performance concrete. Concrete Int1999;21(2):567.

[6] Okamura H. Self-compacting high-performance concrete in Jap-anese Tokyo: Social System Institute; 1999.

[7] Mehta PK. Role of Pozzolanic and cementitious material insustainable development of the concrete industry. ACI SP 1998;178:120.

[8] Neville AM. Properties of concrete. 4th ed. England: LongmanHouse; 1995.

[9] ACI Standard 211.1, Standard practice for selecting proportionsfor normal, heavyweight, and mass concrete. ACI Manual of Concrete Practice, Part 1. 1996. p. 211.1-138.

[10] PCA, Design and Control of Concrete Mixtures. Portland CementAssociation, Skokie, 6th ed. 1995. p. 7994.

[11] de Larrard F. Concrete mixture-proportioning a scientic ap-proach. In: Modern Concrete Technology Series, vol. 9. London:E & FN SPON; 1999. p. 421.

[12] Chai HW. Design and testing of self-compacting concrete. Ph.D.Thesis. University of London, London, 1998.

[13] Bharatkumar BH, Narayanan R, Raghuprasad BK, Ramachan-dramurthy DS. Mix proportion of high-performance concrete.Cement Concrete Compos 2001;23:7180.

[14] Su N, Hsu KC, Chai HW. A simple mix design method for self-compacting concrete. Cement Concrete Res 2001;31:1799807.

[15] ACI Committee 318, Building Code Requirements for ReinforcedConcrete. Building Code Commentary, ACI 318R, 1995.

[16] Kao CC, Hsu KC, Su N. Effects of superplasticizer and Pozzol-anic materials on properties of medium strength high-performanceconcrete. Taipei: Chinese Society of Structural Engineering;1999.

[17] Hon NC. In: Flowing concrete. Beijing, China: China RailwayPub; 1988. p. 14682.

[18] Okamura H. Self-compacting high-performance concrete. Con-crete Int. 1997;19(7):504.

[19] Wu CW, Lein FJ. In: High-performance concrete. Beijing: ChinaRailway Pub; 1999. p. 179.

[20] JASS T-503, Recommendations for Mix Design and ConstructionPractice of High Fluidity Concrete. Japanese Architecture Society,Tokyo: Gihoudou Pub.; 1997.


Documents

1-s2.0-S0958946502000136-main-libre